Subsections

- Library
- Description
- Dialog Box
- Default properties
- Interfacing function
- Computational function (type 4)

##
Sum

### Library

Linear

### Description

### Dialog Box

Set sum block parameters |
Number of inputs or sign vector (of +1, -1) | [1;-1]

- Number of inputs or sign vector :Select this parameter to require that all inputs must have the same data type.

### Default properties

- always active: no
- direct-feedthrough: yes
- zero-crossing: no
- mode: no
- number/sizes of inputs: 2 / -1 -1
- number/sizes of outputs: 1 / -1
- number/sizes of activation inputs: 0 /
- number/sizes of activation outputs: 0 /
- continuous-time state: no
- discrete-time state: no
- name of computational function: summation

### Interfacing function

`scilab/macros/scicos_blocks/linear/SUMMATION.sci`

### Computational function (type 4)

    #include "scicos_block.h"
    #include <math.h>

    void summation(scicos_block *block,int flag)
    {
      int j,k;
      if(flag==1){
        if (block->nin==1){
          block->outptr[0][0]=0.0;
          for (j=0;j<block->insz[0];j++) {
    	block->outptr[0][0]=block->outptr[0][0]+block->inptr[0][j];
          }
        }
        else {
          for (j=0;j<block->insz[0];j++) {
    	block->outptr[0][j]=0.0;
    	for (k=0;k<block->nin;k++) {
    	  if(block->ipar[k]>0){
    	    block->outptr[0][j]=block->outptr[0][j]+block->inptr[k][j];
    	  }else{
    	    block->outptr[0][j]=block->outptr[0][j]-block->inptr[k][j];
    	  }
    	}
          }
        }
      }
    }